of/flattree: Eliminate need to provide early_init_dt_scan_chosen_arch

This patch refactors the early init parsing of the chosen node so that
architectures aren't forced to provide an empty implementation of
early_init_dt_scan_chosen_arch.  Instead, if an architecture wants to
do something different, it can either use a wrapper function around
early_init_dt_scan_chosen(), or it can replace it altogether.

This patch was written in preparation to adding device tree support to
both x86 ad MIPS.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: David Daney <ddaney@caviumnetworks.com>

1 files changed, 10 insertions, 2 deletions

diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index fed9bf6187d1..e296aae63c60 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -363,10 +363,15 @@ static int __init early_init_dt_scan_cpus(unsigned long node,
         return 0;
 }
 
-void __init early_init_dt_scan_chosen_arch(unsigned long node)
+int __init early_init_dt_scan_chosen_ppc(unsigned long node, const char *uname,
+                                         int depth, void *data)
 {
         unsigned long *lprop;
 
+        /* Use common scan routine to determine if this is the chosen node */
+        if (early_init_dt_scan_chosen(node, uname, depth, data) == 0)
+                return 0;
+
 #ifdef CONFIG_PPC64
         /* check if iommu is forced on or off */
         if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
@@ -398,6 +403,9 @@ void __init early_init_dt_scan_chosen_arch(unsigned long node)
         if (lprop)
                 crashk_res.end = crashk_res.start + *lprop - 1;
 #endif
+
+        /* break now */
+        return 1;
 }
 
 #ifdef CONFIG_PPC_PSERIES
@@ -679,7 +687,7 @@ void __init early_init_devtree(void *params)
          * device-tree, including the platform type, initrd location and
          * size, TCE reserve, and more ...
          */
-        of_scan_flat_dt(early_init_dt_scan_chosen, NULL);
+        of_scan_flat_dt(early_init_dt_scan_chosen_ppc, NULL);
 
         /* Scan memory nodes and rebuild MEMBLOCKs */
         memblock_init();